Evolution in Surgical Approach, Complications, and Outcomes in an Adult Spinal Deformity Surgery Multicenter Study Group Patient Population.

STUDY

DESIGN

Retrospective review of a prospectively collected multicenter database.

OBJECTIVES

To evaluate the evolution of surgical treatment strategies, complications, and patient-reported outcomes for adult spinal deformity (ASD) patients.

SUMMARY OF BACKGROUND DATA: ASD surgery is associated with high complication rates. Evolving treatment strategies may reduce these risks.

METHODS

Adult patients undergoing ASD surgery from 2009 to 2016 were analyzed (n = 905). Preoperative and surgical parameters were compared across years. Subgroup analysis of 436 patients with minimum two-year follow-up was also performed.

RESULTS

From 2009 to 2016, there was a significant increase in the mean preoperative age (52 to 63.1, p < .001), body mass index (26.3 to 32.2, p = .003), Charlson Comorbidity index (1.4 to 2.2, p < .001), rate of previous spine surgery (39.8% to 53.1%, p = .01), and baseline disability (visual analog scale [VAS] back and leg pain) scores (p < .01), Oswestry Disability Index, and 22-item Scoliosis Research Society Questionnaire scores (p < .001). Preoperative Schwab sagittal alignment modifiers and overall surgical invasiveness index were similar across time. Three-column osteotomy utilization decreased from 36% in 2011 to 16.7% in 2016. Lateral lumbar interbody fusion increased from 6.4% to 24.1% (p = .004), anterior lumbar interbody fusion decreased from 22.9% to 16.7% (p = .043), and transforaminal lumbar interbody fusion/posterior lumbar interbody fusion utilization remained similar (p = .448). Use of recombinant human bone morphogenetic protein-2 (rhBMP-2) in 2012 was 84.6%, declined to 58% in 2013, and rebounded to 76.3% in 2016 (p = .006). Tranexamic acid use increased rapidly from 2009 to 2016 (13.3% to 48.6%, p < .001). Two-year follow-up sagittal vertical axis, pelvic tilt, pelvic incidence-lumbar lordosis, and maximum Cobb angles were similar across years. Intraoperative complications decreased from 33% in 2010 to 9.3% in 2016 (p < .001). Perioperative (<30 days, <90 days) complications peaked in 2010 (42.7%, 46%) and decreased by 2016 (24.1%, p < .001; 29.6%, p = .007). The overall complication rate decreased from 73.2% in 2008-2014 patients to 62.6% in 2015-2016 patients (p = .03). Two-year health-related quality of life outcomes did not significantly differ across the years (p > .05).

CONCLUSIONS

From 2009 to 2016, despite an increasingly elderly, medically compromised, and obese patient population, complication rates decreased. Evolving strategies may result in improved treatment of ASD patients.

LEVEL OF EVIDENCE: Level IV.